Solt Machine

ABSTRACT

Upon the start of a free game, a processor classifies symbols positioned on reels into an alphabetical character symbol group and an illustrated symbol group. Also, the processor changes the background color of the symbols into red or blue, with respect to each group. Meanwhile, the processor accepts betting for a side bet. After that, the processor repositions fifteen symbols positioned at the free game so as to make the symbols of the same group adjacent to each other. A second prize is awarded if the group selected at the side bet matches the group to which the largest number of symbols is classified among the groups to which the positioned symbols belong.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based upon and claims a priority from the prior Japanese Patent Application No. 2007-272848 filed on Oct. 19, 2007, the entire contents of which are incorporated herein by reference.

BACKGROUND

1. Field

The present invention relates to a slot machine that executes a sub game besides a main game in which a first prize is awarded based on the symbol combination and that further awards a second prize to a player based on the result of the sub game executed.

2. Description of Related Art

Conventionally, in a slot machine, which is one type of gaming machine, a game is started by inserting coins or the like in the gaming machine. In the game, a symbol column is variably displayed in a predetermined area in the gaming machine, and after the lapse of a predetermined period of time, the symbol column is stopped and displayed. Then, a payout is awarded based on a combination of the symbols thus stopped.

Generally, whether or not a winning combination for which a payout is awarded is established is determined depending on whether a predetermined number of symbols of a same kind (for instance, “CHERRY” and “7”) is positioned along a pay line set in advance. Conventionally, if a predetermined number or more of symbols of a same kind is positioned, a payout is also awarded based on the number of symbols thus positioned, irrespective of the pay line.

In a conventional slot machine, video reels or mechanical reels are employed to display a total of fifteen symbols (3×5). In such a slot machine, when a game is started, the reels are rotated, and in conjunction therewith, the symbols of each column arranged vertically start to vary. Then after every lapse of a predetermined time, the reels are stopped and three symbols in each column are displayed therewith. If the symbols are stopped in a combination in which there are at least a predetermined number of symbols of a same kind, a prize is awarded.

Further, in a conventional slot machine, a sub game, is executed besides a main game in which a prize is awarded based on a symbol combination as is described above. Here, a sub game to be executed is, for example, an up-down game, a concentration game, and the like. The slot machine executing the sub game awards the second prize to the player in addition to the first prize of the main game, based on the game result of the executed sub game.

However, in the above-described conventional slot machine, it deteriorates the game tempo to execute as a sub game a game completely different from the main game which uses symbols displayed on the symbols. In addition, a different lottery program and image process program must be executed in the main game and the sub game. This increases the processing load on the processor.

The object of the present invention is to provide a slot machine in which an unprecedented new kind of sub game using symbols displayed on the display device is executed and a second prize is awarded to the player based on the game result of the sub game. This makes it possible to diversify game variations, while reducing the processing load on the processor.

SUMMARY

Therefore, in order to achieve the object, according to a slot machine of the present invention encompassing one or more aspects thereof, there is provided a slot machine comprising a display positioning thereon a plurality of symbols, each classified into some one of a plurality of groups respectively; an operation unit accepting an operation of a player; and a processor. The processor accepts a side bet selecting one of the plurality of groups based on an operation of the bet acceptance button. The processor positions a plurality of symbols on the display. The processor identifies one of the plurality of groups having a largest number of the plurality of symbols displayed on the display classified thereto. The processor repositions the plurality of symbols so that symbols classified into a same group are positioned adjacent to each other. The processor awards a first prize based on combination of the plurality of symbols positioned on the display. The processor awards a second prize in addition to the first prize if the side bet is accepted and simultaneously the one of the plurality of groups selected at the side bet matches the one of the plurality of groups identified. As a result, it becomes possible to execute a sub game of an unprecedented new kind using symbols displayed on the display device in the slot machine. Accordingly, the slot machine can avoid the deterioration of the game tempo, thus the entertainment characteristic of the slot machine can be increased. Further, there is no need to execute different lottery programs or image process programs in the main game and the sub game, making it possible to reduce the processing load on the processor.

According to the present invention encompassing one or more aspects, there is provided a slot machine. The slot machine comprises a display positioning thereon a plurality of symbols, each classified into some one of a plurality of groups respectively; an operation unit accepting an operation of a player; and a processor. The processor selects one of the plurality of groups based on the operation of the player accepted by the operation unit. The processor positions a plurality of symbols on the display. The processor identifies one of the plurality of groups having the plurality of symbols displayed on the display classified thereto. The processor repositions the plurality of symbols so that symbols classified into a same group are positioned adjacent to each other. The processor awards a first prize based on combination of the plurality of symbols positioned on the display. The processor awards a second prize based on the one of the plurality of groups selected and the one of the plurality of groups identified. As a result, plural symbols positioned once on the display are repositioned so that the symbols classified into the same group are placed adjacent to each other. Accordingly, the player can easily judge whether the condition for a prize of the sub game is satisfied or not.

Furthermore, according to the present invention encompassing one or more aspects, there is provided a slot machine. The slot machine comprises a display positioning thereon a plurality of symbols, each classified into some one of a plurality of groups respectively; a bet acceptance button accepting a bet operation; and a processor. The processor accepts a side bet selecting one of the plurality of groups based on an operation of the bet acceptance button. The processor positions a plurality of symbols on the display. The processor identifies one of the plurality of groups having a largest number of the plurality of symbols displayed on the display classified thereto. The processor repositions the plurality of symbols so that symbols classified into a same group are positioned adjacent to each other. The processor awards a first prize based on combination of the plurality of symbols positioned on the display. The processor awards a second prize in addition to the first prize if the side bet is accepted and simultaneously the one of the plurality of groups selected at the side bet matches the one of the plurality of groups identified. As a result, plural symbols positioned on the display are repositioned so that the symbols classified into the same group are placed adjacent to each other. Accordingly, the player can easily grasp in which group the largest number of symbols is classified. In addition, the player can easily judge whether or not the group selected at the side bet matches the group in which the largest number of symbols are classified, namely, whether or not the condition for a prize of the sub game is satisfied.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the objects, advantages and principles of the invention.

FIG. 1 is an explanatory view showing a characteristic part of a slot machine according to an embodiment of the present invention;

FIG. 2 is a perspective view showing an outer appearance of a slot machine according to an embodiment of the present invention;

FIG. 3 is a front view showing a symbol display portion of a slot machine according to an embodiment of the present invention;

FIG. 4 shows a symbol column arranged on each reel during a base game in a slot machine according to an embodiment of the present invention;

FIG. 5 is a view showing a list of contents for various symbols and payouts which are employed in a slot machine according to an embodiment of the present invention;

FIG. 6 is a block diagram showing an internal configuration of an entire slot machine according to an embodiment of the present invention;

FIG. 7 is a block diagram showing an internal configuration of, specifically, a sub-control board in a slot machine according to an embodiment of the present invention;

FIG. 8 is an explanatory view showing a base game, a free game and a sub game which are executed in a slot machine according to an embodiment of the present invention;

FIG. 9 is a flowchart showing a main control process program executed in the slot machine according to an embodiment of the present invention;

FIG. 10 is a flowchart showing a main game process program executed in the slot machine according to an embodiment of the present invention;

FIG. 11 is a flowchart showing a free game process program executed in the slot machine according to an embodiment of the present invention;

FIG. 12 is a flowchart showing a sub game process program executed in the slot machine according to an embodiment of the present invention;

FIG. 13 is a view showing a game result of a sub game in the slot machine according to an embodiment of the present invention; and

FIG. 14 is a perspective view showing an outer appearance of a slot machine according to another embodiment of the present invention.

DETAILED DESCRIPTION

The various aspects summarized previously may be embodied in various forms. The following description shows by way of illustration of various combinations and configurations in which the aspects may be practiced. It is understood that the described aspects and/or embodiments are merely examples, and that other aspects and/or embodiments may be utilized and structural and functional modifications may be made, without departing from the scope of the present disclosure.

It is noted that various connections are set forth between items in the following description. It is noted that these connections in general and, unless specified otherwise, may be direct or indirect and that this specification is not intended to be limiting in this respect.

A slot machine according to one or more aspects of the invention will be described in detail with reference to the drawings based on an embodiment embodying one or more aspects of the invention. However, it is appreciated that one or more aspects of the present invention may be embodied in distributable (via CD and the like) or downloadable software games, console games, and the like. In this regard, the slot machine may be a virtual slot machine that is displayed on a multi-purpose computer and/or dedicated kiosk. Aspects of the invention are described by way of hardware elements. However, it is appreciated that these elements may also be software modules that are executable in a computer. The software modules may be stored on a computer readable medium, including but not limited to a USB drive, CD, DVD, computer-readable memory, tape, diskette, floppy disk, and the like. For instance, aspects of the invention may be embodied in a JAVA-based application or the like that runs in a processor or processors. Further, the terms “CPU”, “processor”, and “controller” are inclusive by nature, including at least one of hardware, software, or firmware. These terms may include a portion of a processing unit in a computer (for instance, in multiple core processing units), multiple cores, a functional processor (as running virtually on at least one of processor or server, which may be local or remote). Further, in network-based gaming systems, the processor may include only a local processor, only a remote server, or a combination of a local processor and a remote server.

It is contemplated that one or more aspects of the invention may be implemented as computer executable instructions on a computer readable medium such as a non-volatile memory, a magnetic or optical disc. Further, one or more aspects of the invention may be implemented with a carrier signal in the form of, for instance, an audio-frequency, radio-frequency, or optical carrier wave.

Next, a detailed description will be given oh an embodiment relating to a slot machine according to the present invention, while referring to the accompanying drawings. The slot machine according to the present embodiment to be described hereinafter is a so-called video slot machine which has an image display device such as a liquid crystal display and in which a game is executed by displaying various kinds of symbol image on the image display device.

The slot machine according to the present invention carries out plural game modes. These game modes include a base game in which gaming values are consumed in accordance with a bet amount on which a bet was placed by the player; a free game which is carried out without the consumption of any gaming values; and a sub game which is executed when a side bet is made during a free game. A prize is awarded in accordance with a game result of the sub game.

For instance, FIG. 1 shows an example in which the present invention is applied to a slot machine according to an embodiment, this slot machine having five reels 13 to 17 provided on a display. When a base game is started in the slot machine shown in FIG. 1, the reels 13 to 17 start to rotate and the symbol columns on the respective reels are displayed in a scrolled manner.

Then, after the lapse of a predetermined period of time, the rotating reels 13 through 17 are stopped in turn starting from left, and fifteen symbols are displayed onto the respective symbol display areas. When a predetermined condition is satisfied, a free game is executed instead of a base game.

When the free game is started, the slot machine starts a side bet acceptance process in which a side bet is accepted. Here, a bet object on which a player can place a bet is either “red” or “blue”. In the free game this time, a sub game is won when there are stopped and displayed more symbols with the background color on which the player has betted, for example, red, than symbols with other background colors, for example, blue. Upon winning the sub game, the player is awarded the second prize in addition to the first prize in the main game.

Meanwhile, in the slot machine according to the present embodiment, fifteen symbols positioned once on a display are repositioned so as to gather the symbols with the same background color. Accordingly, the player can visually grasp with ease which symbol is dominant in number among the symbols stopped and displayed, comparing the symbols with the background color on which the player has betted and the symbols with other background colors.

Hereinafter, a schematic configuration of the slot machine 1 according to the present embodiment will be described based on FIG. 2. FIG. 2 is a perspective view showing an outer appearance of the slot machine 1 according to the present embodiment.

The slot machine 1 according to the present embodiment is an upright-type slot machine installed in a gaming arcade such as a casino or the like. This slot machine 1 has a cabinet 2, a main door 3 provided at a front face of the cabinet 2, and a topper effect device 4 arranged at an upper side of the cabinet 2.

The cabinet 2 is a housing portion that houses electrical or mechanical components. These electrical or mechanical components are used in execution of a predetermined game aspect.

The main door 3 has an upper display portion 10A, a mid-stage variable display portion 10B and a lower display portion 10C, functioning as a display portion 10 that displays information with respect to the game. The upper display portion 10A has an upper liquid crystal panel 11A which is arranged at an upper side of the variable display portion 10B. The upper liquid crystal panel 11A displays, for instance, effect images, an introduction to the game contents, explanation of game rules, payout tables, a sub game result to be later described and the like. The lower display portion 10C is arranged at a lower side of the variable display portion 10B and has a plastic panel 11C onto which an image has been printed. This plastic panel 11C is lit up with a backlight.

The variable display portion 10B that displays an execution state of the game has a main liquid crystal panel 11B constituted of a heretofore known transparent liquid crystal panel which is fixedly mounted to the main door 3. Here, the main liquid crystal panel 11B is constituted of a heretofore known liquid crystal panel and has a symbol display portion 12 which comprises a 3×5 symbol display area. The symbol display portion 12 is constituted of five reels 13 through 17. With respect to the respective reels 13 through 17, the symbol columns with the alignment set in advance (FIG. 4) are displayed in a scrolled manner during a base game and a free game, and after the lapse of a predetermined period of time, three symbols are respectively stopped and displayed in each reel. As a result, fifteen symbols are displayed in accordance with the progress of the game as will be described later, and a predetermined payout is awarded to the player in accordance with the combination of the displayed symbols and the credit amount (bet amount) thus betted. The number of reels may be three, and further, the number of displayed symbols is not limited to fifteen. In addition, during the free game, specifically, the positions of the fifteen symbols stopped and displayed with the respective reels 13 through 17 once positioned are changed so as to place the symbols with a same background color adjacent to each other.

Further, a touch panel 18 is provided at a front face of the main liquid crystal panel 11B. The player can operate the touch panel 18 to input various types of commands.

At a right lower side of the variable display portion 10B, there are provided a payout amount display portion 19 and a credit amount display portion 20. The payout amount display portion 19 displays, as a payout amount, a payout amount to hp awarded in a case where the symbol combination which is stopped and displayed on the pay line in a base game is a predetermined combination, and an accumulated payout amount acquired in a free game. The credit amount display portion 20 displays the credit amount that the player currently possesses.

The cabinet 2 has an operation table 25 provided at a front face thereof, between the variable display portion 10B and the lower display portion 10C, and bulging out at the front side. On this operation table 25 are arranged various kinds of operation buttons 26, forming an operation unit that commands execution of the game. The buttons 26 include a BET button, a COLLECT button, a START button, a CASHOUT button and the like. The operation table 25 has a coin slot 27 adapted to accept coins, representing gaming values, inside the cabinet 2, and a bill slot 28 adapted to accept bills inside the cabinet 2.

The slot machine 1 according to the present embodiment employs coins, bills or electronic value information (credit) corresponding to these, as gaming values. The gaming values applicable to the present invention are not limited to those described above, and can include, for instance, medals, tokens, electronic money and tickets.

At a lowermost part of the cabinet 2, there is provided a coin tray 29 adapted to accept coins paid out from the hopper. Further, at a periphery of the cabinet 2 in the slot machine 1, there is arranged a light emitting portion 30 which lights up in a predetermined lighting fashion during a free game, or if a win occurs. Further, at a side face of the cabinet 2 is provided a speaker 31 for audio output.

Further, the slot machine 1 has a topper effect device 4 provided at an upper side of the cabinet 2. This topper effect device 4 has a rectangular board shape and is arranged so as to be substantially parallel with the upper liquid crystal panel 11A of the upper display portion 10A.

Next, a symbol display portion 12 provided in the main liquid crystal panel 11B and symbols 21A through 21D, 22A and 22B to be displayed on the symbol display portion 12 will be described based on FIG. 3 through FIG. 5. FIG. 3 is a front view showing a symbol display portion 12 in a slot machine according to the present embodiment. FIG. 4 shows a symbol column arranged on each reel in a slot machine according to the present embodiment of the present invention. FIG. 5 is a view showing a list of contents for various symbols and payouts which are used during a game and free game in a slot machine according to the present embodiment of the present invention.

First, the symbol display portion 12 and symbols 21A through 21D, 22A and 22B displayed on the symbol display portion 12 during the execution of the base game, will be described. The symbol display portion 12 according to the present embodiment is constituted of five reels 13 through 17. The reels 13 through 17 each have symbol display areas 32 through 46, each symbol display area respectively displaying three symbols to the symbol display portion 12 when the respective rotating reels 13 through 17 are stopped. In the present embodiment, six kinds of scatter symbol are used, specifically, “A” symbol 21A, “K” symbol 21B, “Q” symbol 21C, “J” symbol 21D, “SUN” symbol 22A, and “THUNDER” symbol 22B, as shown in FIGS. 4 and 5. When a game is started, the respective symbol display areas 32 through 46 each display one symbol (total 15 symbols), as shown at (1) through (4) in FIG. 8. In the drawing, a dotted line is drawn to divide the respective symbol display areas 32 through 46; however, a configuration is possible where the dotted line is not shown.

Next, the symbol columns displayed in a scrolled manner with the rotation of the reels 13 through 17 at the slot machine according to the present embodiment will be described.

As shown in FIG. 4, each of the reels 13 through 17 includes a total of ten symbols, with a predetermined number of “A” symbol 21A, “K” symbol 21B, “Q” symbol 21C, “J” symbol 21D, “SUN” symbol 22A, and “THUNDER” symbol 22B, respectively combined. During a base game, the background color is white in all the symbols 21A through 21D, 22A and 22B. In contrast, during a free game, the background color becomes red in alphabetical character symbols 21A through 21D, and blue in illustrated symbols 22A and 22B. The slot machine 1 executes a later-described sub game using these different background colors.

Regarding respective symbol columns on the reels 13 through 17, a code number is assigned to each of the symbols in order from top one and code numbers are used in a lottery process so as to determine symbols to be positioned in the symbol display areas 32 through 46.

Next, various kinds of winning combinations to be established based on the symbols 21A through 21D, 22A and 22B positioned in the symbol columns area 12 will be described in detail while referring to FIG. 5.

One “A” symbol 21A is included in each of all symbol columns of reels 13 through 17. If four “A” symbols are positioned in the symbol display areas 32 through 46, 10 credits are paid out to the player, as a payout. If five “A” symbols are positioned in the symbol display areas 32 through 46, 50 credits are paid out to the player, as a payout. Further, if four “A” symbols or more are displayed in the symbol display areas 32 through 46, free games are successively carried out by a predetermined number of times (for instance, 5 times), as a payout, after the end of the base game.

One “K” symbol 21B is included in each of all symbol columns of reels 13 through 17. If four “K” symbols are positioned in the symbol display areas 32 through 46, 7 credits are paid out to the player, as a payout. If five “K” symbols are positioned in the symbol display areas 32 through 46, 30 credits are paid out to the player, as a payout.

Similarly, as of “Q” symbols 21C, “J” symbols 21D, “SUN” symbols 22A and “THUNDER” symbols 22B, if four or five symbols of a same kind are displayed in the symbol display areas 32 through 46, the payout shown in FIG. 5 is paid out.

Meanwhile, FIG. 5 illustrates the payout amount when the bet amount at the start of the game is one bet. Accordingly, if the bet amount is more than one, the amount obtained by multiplying the payout corresponding to FIG. 5 by the bet amount is awarded to the player.

In the present embodiment, a winning combination is established if the same kind of symbol is displayed by a predetermined number of times in the symbol display areas 32 through 46 irrespective of the pay line, and in a case only scatter symbols have been constituting symbols. In this case, a payout is awarded. A payout may also be awarded for a win according to a pay line. In that case, a payout may be awarded if the same kind of symbol is displayed by a predetermined number of times along the pay line. Also, both a payout depending on the pay line and a payout irrespective of the pay line may be awarded.

Next, the internal configuration of the above-mentioned slot machine 1 will be described while referring to FIG. 6 and FIG. 7. FIG. 6 is a block diagram showing an internal configuration of the entire slot machine 1. As shown in FIG. 6, the slot machine 1 has a plurality of constituent elements arranged around a main control board 71 including a controller 51 that executes control programs that will be described later (FIG. 9 through FIG. 12). The main control board 71 has a controller 51, a random number generation circuit 55, a sampling circuit 56, a clock pulse generation circuit 57, a divider 58, an illumination effect driving circuit 61, a hopper driving circuit 63, a payout completion signal circuit 65 and a display portion driving circuit 67.

The controller 51 has a main CPU 52, a RAM 53 and a ROM 54. The main CPU 52 operates in accordance with the programs stored in the ROM 54 and performs signal input and output with respect to the other constituent elements through an I/O port 59. Specifically, the main CPU 53 controls the operation of the entire slot machine 1. The RAM 53 stores data and programs to be used when the main CPU 52 is operating. For instance, the RAM 53 temporarily retains the random number values which have been sampled by the sampling circuit 56 after the game has started. The RAM 53 stores code numbers corresponding to the respective reels 13 through 17. The ROM 54 stores various types of programs that will be executed by the main CPU 52, as well as permanent data.

More particularly, the programs stored in the ROM 54 include game programs and game system programs (hereinafter referred to as game programs or the like). Further, the game programs include lottery programs as will be described later.

The lottery programs are used to determine the code numbers for the respective reels 13 through 17 corresponding to the respective symbols which are re-positioned on the main liquid crystal panel 11B. This lottery program includes symbol weighing data for each of the respective five reels 13 through 17. The symbol weighing data shows correspondence relationships between the respective code numbers and one or a plurality of random number values within a predetermined number value range (for instance 0 through 255). The probability of lottery with respect to each symbol is set by associating one or a plurality of random number values to one code number. The random number values are drawn by lottery and symbols which have been finally identified from the random number values are re-positioned on the main liquid crystal panel 11B.

The lottery program for determining the symbols to be positioned may also employ weighing data in which the predetermined random number range is associated to the symbol combination. In this case, first, the symbol combination is selected by lottery based on the lottery program, and thereafter, the symbol combination thus determined is re-positioned in the main liquid crystal panel 11B.

The random number generation circuit 55 operates in accordance with the commands from the main CPU 52 and generates random numbers within a predetermined range. The sampling circuit 56 selects, by lottery, an arbitrary random number from the random numbers generated by the random number generation circuit 55 in response to a command from the main CPU 52. At the same time, the sampling circuit 56 inputs the random number thus selected to the main CPU 52. The clock pulse generation circuit 57 generates a reference clock for causing the main CPU 52 to operate. The divider 58 inputs a signal obtained by dividing the reference clock by a constant frequency to the main CPU 52.

The main control board 71 is connected to the touch panel 18. The touch panel 18 is arranged at a front face of the main liquid crystal panel 11B and is adapted to identify a coordinate position of the portion that was touched by the player. Specifically, the touch panel 18 can discriminate the portion that the player has touched, and in what direction the touched portion was moved based on the coordinate position information that was thus identified. A signal in accordance with the above discrimination is then inputted to the main CPU 52 through the I/O port 59.

The main control board 71 is connected to the operation buttons 26, including a START button for commanding execution of a game, a COLLECT button, a BET button and the like. Accordingly, a signal in accordance with a depression operation of these buttons is inputted to the main CPU 52 through the I/O port 59.

The illumination effect driving circuit 61 outputs an effect signal for causing the light emitting portion 30 and the topper effect device 4 as mentioned above to perform illumination effects. The topper effect device 4 is connected in series with the illumination effect driving circuit 61 through the light emitting portion 30.

The hopper driving circuit 63 drives the hopper 64 under the control of the main CPU 52. As a result, the hopper 64 carries out an operation to payout coins to the coin tray 29. The payout completion signal circuit 65 receives coin amount value data from the coin detecting portion 24 to which it is connected. Then, when the received coin amount value has reached the set coin amount value, the payout completion signal circuit 65 inputs a signal that notifies the completion of coin payout to the main CPU 52. The coin detecting portion 66 detects the number of coins that were paid out by the hopper 64 and then inputs coin amount value data showing the amount of coins that was detected to the payout completion signal circuit 65. The display portion driving circuit 67 controls the display operation of the respective display portions including the reels 13 through 17, a payout amount display portion 19 and the credit amount display portion 20 and the like.

The main control board 71 is connected to the sub-control board 72. As shown in FIG. 7, the sub-control board 72 carries out display control of the upper liquid crystal panel 11A in the upper display portion 10A and the main liquid crystal panel 11B in the variable display portion 10B, as well as output control of the audio outputted by the speaker 31, based on the commands received from the main control board 71. This sub-control board 72 is constituted on a separate circuit board from the circuit board that constitutes the main control board 71. The sub-control board 72 has a micro computer (hereinafter referred to as “sub-micro computer”) 73 which is provided as a main constituting element. Then, the sub-control board 72 has a sound source IC 78, a power amplifier 79, and an image control circuit 81. The sound source IC 78 controls the audio output from the speaker 31. The power amplifier 79 functions as an amplifier. The image control circuit 81 operates as a display control section for the upper liquid crystal panel 11A and the main liquid crystal panel 11B.

The sub-micro computer 73 has a sub-CPU 74, a program ROM 75, a work RAM 76 and I/O ports 77 and 80. The sub-CPU 74 carries out a control operation in accordance with a control command transmitted from the main control board 71. Although the sub-control board 72 does not have a clock pulse generation circuit, a divider, a random number generation circuit and a sampling circuit, it is constituted so as to execute sampling of random numbers based on an operation program of the sub-CPU 74. The program ROM 75 stores a control program to be executed by the sub-CPU 74. The work RAM 76 is constituted as a temporary memory to be used by the sub CPU 74 in executing the control program.

The image control circuit 81 has an image control CPU 82, an image control work RAM 83, an image control program ROM 84, an image ROM 86, a video RAM 87 and an image control IC 88. The image control CPU 82 determines the image to be displayed on the upper liquid crystal panel 11A and the main liquid crystal panel 11B based on the parameters set in the sub-micro computer 73 and the image control programs stored in the image control program ROM 84. For instance, the upper liquid crystal panel 11A displays a payout table, a help screen and a sub game result screen (FIG. 13). The main liquid crystal panel 11B carries out scrolled display and stopped display of the respective symbols 21A through 21D, 22A and 22B concurrent with the rotation of the reels 13 through 17 in a base game and free game, with respect to the symbol display portion 12.

The image control program ROM 84 stores an image control program and various types of selection tables relating to display on the upper liquid crystal panel 11A and the main liquid crystal panel 11B. The image control work RAM 83 functions as a temporary memory to be used in execution of the image control program in the image control CPU 82. The image control IC 88 forms an image in accordance with the contents determined by the image control CPU 82 and then outputs the image thus formed to the upper liquid crystal panel 11A and the main liquid crystal panel 11B.

The image ROM 86 stores dot data for forming an image. The video RAM 87 functions as a temporary memory to be used by the image control IC 88 in forming an image.

Next, the base game and the free game which are carried out in the slot machine 1 having the above configuration will be described referring to FIG. 8. First, the base game will be described. The base game is a slot game in which a predetermined symbol combination is repositioned on the main liquid crystal panel 11B, through the respective reels 13 through 17. More specifically, the player operates an operation button 26 to set the bet amount, and when he/she depresses the START button, a lottery processing is executed to select, by lottery, the symbols that will be positioned in the symbol display portion 12. After the start button has been depressed and the reels 13 through 17 start rotating following the lapse of a predetermined period of time, the symbol columns are displayed in a scrolled manner (refer to FIG. 8 (1)). On the reels 13 through 17 there are arranged the respective symbols 21A through 21D, 22A and 22B in an alignment shown in FIG. 4. Then, as shown in FIG. 8 (2), after the lapse of a predetermined period of time, a total of fifteen symbols will be stopped and displayed in stages in the symbol display areas 32 through 46.

Here, in the base game, various kinds of winning combinations are determined in advance based on the respective symbol combinations re-positioned in the main liquid crystal panel 11B (refer to FIG. 5). If a symbol combination corresponding to the winning combination is realized through the symbols re-positioned in the symbol display areas 32 through 46, a gaming value obtained by multiplying the payout corresponding to the winning combination thus established by the bet amount is awarded to the player.

On the other hand, the free game carried out in the slot machine executed after the game mode has switched from the base game in a case where a winning combination, including at least four “A” symbols 21A, has been positioned in the symbol display areas 32 through 46. After the game has been successively carried out by a predetermined number of times (for instance, 5 times), the free game ends and the game mode switches again to the base game. With respect to the procedure of the game, the free game is the same as the base game, except that in the free game, gaming values (credits) corresponding to the bet amount are not consumed at the start of the game, and the game is continuously carried out automatically without requiring the player to operate the operation button 26. However, during a free game, a sub game is executed concurrently when a side bet is betted.

Specifically, when a free game starts, each of the symbols 21A through 21D, 22A and 22B, which are arranged on the reels 13 through 17, is classified into two groups. To be specific, the symbols are classified into alphabetical character symbols 21A through 21D and illustrated symbols 22A and 22B other than the alphabetical character symbols. Then, as shown in FIG. 8 (3), the background color of alphabetical character symbols 21A through 21D is turned from white to red according to the classified group. At the same time, the background color of illustrated symbols 22A and 22B is turned from white to blue. Under the condition of the changed background colors, symbol columns are scroll-displayed (refer to FIG. 8 (4)).

When the scroll-display of symbol columns starts at the free game, a side bet acceptance period starts as shown in FIG. 1 (1). The side bet acceptance period is a period for accepting a side bet. Here, the betting object on which the player makes a side bet is either “red” or “blue”.

After that, similarly to the base game, a total of fifteen symbols are gradually stopped and displayed in the symbol display areas 32 through 46 after the lapse of the predetermined time period, as shown in FIG. 1(2). If a symbol combination corresponding to the winning combination is established by the symbols repositioned in the symbol display area 32 through 46, the player is awarded as a first prize a gaming value, the amount of which is obtained by multiplying the payout according to the established winning combination by the bet amount.

Meanwhile, if a side bet is accepted, the fifteen symbols once positioned in the symbol display portion 12 are repositioned so as to place the symbols with the same background color (red or blue) adjacent to each other (refer to FIG. 1 (3)).

Then, if the symbols with the background color (e.g., red) on which the player has placed a bet are displayed in the symbol display portion 12 in larger number than the symbols with another color (e.g., blue), the player wins a sub game, and is awarded a second prize in addition to the first prize (refer to FIG. 1(4)).

Next, a main control program to be executed in the slot machine 1 according to the present embodiment will be described in detail while referring to the drawings. FIG. 9 is a flow chart showing a main control program.

First, when the power switch is turned on (upon power on), the main control board 71 activates the sub-control board 72 and the controller 51 executes an initial setting process at step (hereinafter referred to as S) 1. In the initial setting process, the main CPU 52 executes the BIOS stored in the ROM 54 and expands the compressed data incorporated in the BIOS in the RAM 53. In executing the BIOS that was expanded in the RAM 53, the main CPU 52 carries out a diagnosis and initialization of the different types of peripheral devices. Further, the main CPU 52 writes the game programs and the like from the ROM 54 into the RAM 53 to acquire payout rate setting data and country identification information. While executing the initial setting process, the main CPU 52 also carries out an authentication process with respect to each program.

Then, at S2, the main CPU 52 sequentially reads the game programs and the like from the RAM 53 and executes these programs to carry out a main game process. The slot machine 1 according to the present embodiment carries out the game by executing this main game process. The main game process is repeatedly executed while power is supplied to the slot machine 1.

Next, a sub-process of the main game process at the above-described S2 will now be described based on FIG. 10. FIG. 10 is a flow chart of a main game process program to be executed in the slot machine 1 according to the present embodiment. The programs shown in the flow charts at FIG. 10 and FIG. 11 as will be described later are stored in the ROM 54 and RAM 53 provided in the slot machine 1 and are executed in the main CPU 52.

As shown in FIG. 10, the main CPU 52 first executes a start acceptance process at S11. In the start acceptance process, the player inserts coins and places a bet using the BET button from amongst the operation buttons 26.

At S12, the main CPU 52 determines whether or not the start button from amongst the operation buttons 26 has been depressed. This determination is carried out based on the signal inputted to the main CPU 52 in response to depression of the start button. Here, if the start button has not been depressed (S12: NO), the flow returns to the start acceptance process (S11). As a result, the player can carry out an operation to correct, etc. the bet amount. Alternatively, if the start button has been depressed (S12: YES), the main CPU 52 subtracts the bet amount set based on the above-described bet operation from the credit amount that the player currently possesses and at the same time stores the result as bet information in the RAM 53.

At S13, the main CPU 52 executes a symbol lottery process for the base game. In this symbol lottery process, the main CPU 52 selects, by lottery, the symbols to be positioned on the main liquid crystal panel 11B. More specifically, the main CPU 52 executes the lottery program stored in the RAM 53, thereby sampling a random number value from a number value range within a predetermined random number value range. The main CPU 52 determines the respective fifteen symbols (specifically, stop positions of reels 13 through 17), from amongst the six kinds of scatter symbol 21A through 21D, 22A and 22B that will be re-positioned in the symbol display areas 32 through 46, based on the sampled random number value and the symbol weighing data.

Next, at S14, the main CPU 52 carries out a reel rotation process. Namely, the reels 13 through 17 start rotating and the symbol columns positioned in the respective reels 13 through 17 are displayed in a scrolled manner at a predetermined speed. Then, after the lapse of a predetermined period of time, the rotating reels 13 through 17 are stopped in turn, starting from the left, and one symbol is respectively displayed in each of symbol display areas 32 through 46 (refer to FIG. 8 (2)). Thus, the symbol combination determined at the above-mentioned S13 is re-positioned in the symbol display areas 32 through 46 of the main liquid crystal panel 11B.

Then, at S15, the main CPU 52 carries out a winning determination process to determine whether the symbol combination positioned in the main liquid crystal panel 11B is any of the winning combinations for which a payout is awarded. This determination is carried out based on the code numbers of the respective reels 13 through 17 stored in the RAM 53.

If it is determined, at the above-mentioned S15 that the winning combination has been established (S16: YES), the flow shifts to S17. Alternatively, if it is determined that the winning combination has not been established (S16: NO), the main game process is ended. The processes following S11 are again carried out in a case a game is next started.

At S17, the main CPU 52 calculates a payout based on the winning combination thus established. For instance, if a predetermined number or more of the same kind of symbols have been positioned, as shown in FIG. 5, a payout is calculated in accordance with the kind of symbol and the number of positioned symbols.

Next, at S18, the main CPU 52 notifies the player by displaying the kind of the winning combination thus established and the contents of the payout with respect to the main liquid crystal panel 11B. For instance, if five “A” symbols 21A have been displayed as shown at (2) in FIG. 8, a message “WIN 50” and a message “Go Free Game” are displayed. The former message notifies that 50 credits will be paid out as a payout, and the latter message notifies that the game mode shifts to a free game.

Next, at S19, the main CPU 52 determines whether or not the trigger for shifting to the free game has been established. More specifically, if the winning combination including at least four “A” symbols 21A has been established, a determination is made that the trigger for shifting to the free game has been established.

As a result, if it is determined that the free-game shift trigger has been established (S19: YES), the value for the payout which will be awarded at present is stored (S20), and then, the flow shifts to the free game process (FIG. 11) as will be described later (S21). The payout which is stored at the above-described S20 is to be paid out in the free game as will be described later in a lump sum with other payouts. Alternatively, if it is determined that the free-game shift trigger is not established (S19: NO), the flow shifts to S22.

At S22, the main CPU 52 awards a payout to the player in accordance with the winning combination established in the current game, based on the calculation result of the above-described S17. At this time, the payout can be made using coins corresponding to the credit amount (1 credit corresponds to 1 coin), and the payout can be made using bar-code attached tickets, in response to the depression of the CASHOUT button from among the operation buttons 26. If a free game or a sub game has been carried out, a payout which is accumulated during the free game or the sub game is paid out altogether to the player.

Next, the sub-process for the free game process at the above step S21 will be described based on FIG. 11. FIG. 11 is a flow chart of a sub-process program for the free game process in the slot machine 1 according to the present embodiment.

First, at S31, the main CPU 52 classifies each of the symbols 21A through 21D, 22A and 22B arranged on the reels 13 through 17 into two groups of alphabetical character symbols 21A through 21D and illustrated symbols 22A and 22B other than the alphabetical character symbols. Then, for allowing the discrimination of the groups into which the symbols are classified, the background color of alphabetical character symbols 21A through 21D is turned from white to red and at the same time, the background color of illustrated symbols 22A and 22B is turned from white to blue.

Next, at S32, the main CPU 52 executes a symbol lottery process for a free game in which a lottery is held for the symbols to be positioned on the main liquid crystal panel 11B. The substantial processing method of the lottery process is similar to the symbol lottery process for the base game at the above S13, therefore a detailed description is omitted.

At S33, the main CPU 52 executes a reel rotation process under the condition of the background colors of symbols being changed. Namely, the reels 13 through 17 start rotating and the symbol columns arranged in each of the reels 13 through 17 are displayed in a scrolled manner at a predetermined speed.

Then, at S34, the main CPU 52 executes a side bet acceptance process for accepting a side bet. In this side bet acceptance process, the player carries out operations such as coin insertion or bet operation using the BET button from among the operation buttons 26, a credit of the amount as the player wishes (or a credit of fixed amount) is betted on either “red” or “blue”. It is noted that if a side bet is not accepted at the above S34, the later-described sub game process (S42) is not executed. If a side bet is accepted, the betting object (“red” or “blue”) which has accepted the side bet and betting amount are displayed on the upper liquid crystal panel 11A. For instance, the screen shown in FIG. 1 (2) is a screen displayed when 10 credits are betted on “red”.

Then, after the lapse of a predetermined period of time, the rotating reels 13 through 17 are stopped in turn, starting from the left, and one symbol is displayed in each of the symbol display areas 32 through 46 (S35). As a result, the symbol combination as determined at the above-described S32 is repositioned in the symbol display areas 32 through 46 of the main liquid crystal panel 11B.

Then, at S36, the main CPU 52 carries out a winning determination process in which a determination is made whether or not the symbol combination positioned on the main liquid crystal panel 11B is any of the winning combinations for which any of the payouts is awarded.

If it is determined at S36 that the winning combination has been established (S37: YES), the flow shifts to S38. Alternatively, if it is determined that the winning combination has not been established (S37: NO), the flow shifts to S41.

At S38, the main CPU 52 calculates the first prize, a payout based on the winning combination thus established. For instance, if a predetermined number of symbols of a same kind has been positioned at least a predetermined number, as shown in FIG. 5, a payout is calculated in accordance with the kind of symbol and the number of positioned symbols.

Next, at S39, the main CPU 52 sends a notification to the player by displaying the kind of the winning combination thus established and the contents of the payout, with respect to the main liquid crystal panel 11B (refer to FIG. 1 (2)).

Next, at S40, the main CPU 52 accumulatively stores a payout corresponding to the winning combination established in the current game in the RAM 53, based on the calculation results at the above-described S38. The payout thus stored is awarded to the player altogether, after the free game ends (S22).

Then, at S41, the main CPU 52 determines whether or not a side bet is accepted at the above S34. If it is determined that the side bet is accepted (S41: YES), the flow shifts to S42, and executes the later-described sub game process (FIG. 12). In the sub game process, a win is determined based on the bet information of the side bet and the group to which the symbols positioned in the symbol display portion 12 are classified. Meanwhile, if it is determined that the side bet is not accepted (S42: YES), the flow shifts to S43 without executing the sub game process.

Then, at step S43, the main CPU 52 determines whether or not the free game completion condition has been satisfied. The free game completion condition in the slot machine 1 according to the present embodiment includes the execution of five free games after shifting to the free game.

If it is determined that the free game completion condition has been satisfied (S43: YES), the flow shifts to S44. Alternatively, if it is determined that the free game completion condition is not satisfied (S43: NO), the flow returns to S32 at which the free game is then executed.

At S44, the main CPU 52 changes the background colors which have been changed with respect to the group classified at the above S31 back to the original color, white. Further, the main CPU changes the game mode from the free game to the base game, and then the flow shifts to S22.

The sub-process of the sub-game process at S42 will now be described based on FIG. 12. FIG. 12 is a flow chart of a sub-process program of the sub-game process in the slot machine according to the present embodiment.

At S51, the main CPU 52 first identifies the group to which each of the fifteen symbols is classified. The fifteen symbols have been positioned in the respective symbol display areas 32 through 46 at the above S35. It is noted that the groups to which symbols are classified are the following two groups: a group of alphabetical character symbols and a group of illustrated symbols other than the alphabetical character symbols.

After that, at S52, the main CPU 52 repositions the fifteen symbols once positioned in the respective symbol display areas 32 through 46 based on the groups identified at the above S51, changing the arrangements so as to make symbols classified to the same group placed adjacent to each other (refer to FIG. 1 (3)). Specifically, it repositions symbols 21A through 21D, which belong to the alphabetical character symbol group, orderly in the symbol display areas starting from the symbol display area 32 which locates in the top left. Then the main CPU 52 repositions symbols 22A and 22B, which belong to the illustrated symbol group, in the rest of the symbol display areas. Accordingly, symbols belonging to a certain group are gathered group by group, and positioned in the symbol display portion 12.

Next, at S53, based on the groups identified at the above S51, the main CPU 52 identifies the group to which the largest number of symbols is classified among the groups to which the positioned symbols belong. Then the main CPU 52 judges whether or not the group selected at the side bet accepted at the above S34 matches the group to which the largest number of symbols is classified. If it matches, the sub-game is determined to be won.

Further, at S54, the main CPU 52 displays the game result of the sub-game in the upper liquid crystal panel 11A. Here, FIG. 13 is a view showing the sub game result screen 101 displayed in the upper liquid crystal panel 11A.

As shown in FIG. 13, the sub game result screen 101 displays the number of symbols belonging to the alphabetical character symbol group (indicated as “RED TEAM” in the figure) 102 and the number of symbols belonging to the illustrated symbol group (indicated as “BLUE TEAM” in the figure) 103. As of the group with the larger number of symbols classified (the alphabetical character symbol group, in the figure), the word “WIN!!” 104 is displayed in addition to the number of the symbols. Accordingly by seeing the game result screen 101 displayed on the upper liquid crystal panel 11A, the player can grasp the number of symbols belonging to each group and the group with the larger number of symbols positioned.

If it is determined to have won a sub game with the determination at the above S53 (S55: YES), the flow shifts to S56. Alternatively, if it is determined not to have won a sub game (S55: NO), the main CPU 52 terminates the sub game process and shifts to S43.

At S56, the main CPU 52 calculates the payout amount directed to the winning of the sub game (second prize). Specifically, the gaming value equivalent to twice the betting amount betted at the side bet becomes the second prize.

Next, at S57, the main CPU 52 displays the winning result or the contents of payout on the main liquid crystal panel 11 b, so as to notify the player (refer to FIG. 1 (4)).

Subsequently, at S58, the main CPU 52 stores accumulatively in RAM 53 the payout of the current sub game based on the calculation of the above S56. Then the process shifts to S43. The stored payout is paid out to the player in a lump sum after the end of the free game (S22).

As was described hereinbefore, in the slot machine 1 according to the present embodiment, when a free-game shift trigger is established at the base game (S19: YES), a free game is executed (S21). Upon the start of the free game, the symbols positioned on the reels 13 through 17 are classified into an alphabetical character symbol group and an illustrated symbol group. Also, the background color of symbols is changed into red or blue, with respect to each group (S31). Meanwhile, betting is accepted for a side bet (S34). After that, fifteen symbols positioned at the free game are repositioned so as to make the symbols of the same group adjacent to each other (S52). The second prize is awarded if the group selected at the side bet matches the group to which the largest number of symbols is classified among the groups to which the positioned symbols belong (S22). Accordingly, the slot machine 1 can execute an unprecedented new sub game employing the symbols displayed on the main liquid crystal panel 11B. In addition, the game tempo thereof does not deteriorate even while executing a sub game and the entertainment characteristics of the slot machine can further be improved. Further, a different lottery program or image processing program need not be executed, and the processing load can be reduced.

Also, the main CPU 52 repositions the symbols so that the symbols classified into a same group are repositioned adjacent to each other, thus making it possible for the player to easily grasp the group to which the largest number of symbols is classified. Accordingly, the player can easily judge whether or not the group selected at the side bet matches the group to which the largest number of symbols is classified, namely, whether or not the sub game winning combination is established.

In addition, the main CPU 52 displays, as a sub game result, the number of symbols with respect to the group identified in the upper liquid crystal panel 11A (S54), thus allowing the player to clearly grasp the group to which the largest number of symbols is classified among the symbols positioned in the symbol display portion 12.

Also, the main CPU 52 positions the symbols main liquid crystal panel 11B, using a different background color with respect to the group classified, thus allowing the player to easily grasp visually which group the symbols positioned in the symbol display portion 12 are classified into.

The present invention is not limited to the above-described embodiment and various modifications and alterations can be made thereto without departing from the scope of the present invention.

For instance, in the present embodiment, the conditions for shifting to the free game include establishment of a winning combination including at least a predetermined number of “A” symbols 21A. However, the conditions for shifting to the free game may also include other conditions. For instance, the condition may occur unexpectedly, as a mystery.

In the present embodiment, symbol background colors are unified to a same color with respect to the group to be classified. However, the colors of symbols themselves may be unified to the same color. Or, symbol forms or styles may be unified to a same form or style.

The present invention is not limited to video reels only, but also is applicable with respect to slot machines using mechanical reels. For instance, the slot machine 201 shown in FIG. 14 is a so-called hybrid-type slot machine having a heretofore known transparent liquid crystal panel installed at a front face of the plurality of mechanical reels which are rotatably supported, and a game is carried out therein by displaying images of the respective symbols positioned on the outer periphery of the mechanical reels, through the transparent liquid crystal panel.

The slot machine 201 has 3 reels, a left reel 203, a center reel 204 and a right reel 205 which are rotatably supported. The respective reels 203 through 205 have symbol columns drawn on their outer periphery, each column being made up of plural symbols. Further, the respective reels 203 through 205 have, at a front side thereof, a main liquid crystal panel 202 which is made up of a heretofore known transparent liquid crystal panel provided in the main door. Here, the main liquid crystal panel 202 has three display windows 206, 207, and 208 formed therein, the back sides thereof being visible. When the display windows 206, 207 and 208 are in a transparent state, the symbols drawn on each of reels 203 through 205 are visible.

In the above-described slot machine 201, the base game and the free game may be carried out employing the reels 203 through 205, and the repositioning of the symbols may be carried out displaying the symbols after repositioned in the main liquid crystal panel 202.

Although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims. 

1. A slot machine comprising: a display positioning thereon a plurality of symbols, each classified into some one of a plurality of groups respectively; an operation unit accepting an operation of a player; and a processor executing processes as follows: (a) a process of selecting one of the plurality of groups based on the operation of the player accepted by the operation unit; (b) a process of positioning a plurality of symbols on the display; (c) a process of identifying one of the plurality of groups having the plurality of symbols displayed on the display classified thereto; (d) a process of awarding a first prize based on combination of the plurality of symbols positioned on the display; and (e) a process of awarding a second prize based on the one of the plurality of groups selected at the process (a) and the one of the plurality of groups identified at the process (c).
 2. A slot machine comprising: a display positioning thereon a plurality of symbols, each classified into some one of a plurality of groups respectively; an operation unit accepting an operation of a player; and a processor executing processes as follows: (a) a process of selecting one of the plurality of groups based on the operation of the player accepted by the operation unit; (b) a process of positioning a plurality of symbols on the display; (c) a process of identifying one of the plurality of groups having the plurality of symbols displayed on the display classified thereto; (d) a process of repositioning the plurality of symbols so that symbols classified into a same group are positioned adjacent to each other; (e) a process of awarding a first prize based on combination of the plurality of symbols positioned on the display; and (f) a process of awarding a second prize based on the one of the plurality of groups selected at the process (a) and the one of the plurality of groups identified at the process (c).
 3. A slot machine comprising: a display positioning thereon a plurality of symbols, each classified into some one of a plurality of groups respectively; a bet acceptance button accepting a bet operation; and a processor executing processes as follows: (a) a process of accepting a side bet selecting one of the plurality of groups based on an operation of the bet acceptance button; (b) a process of positioning a plurality of symbols on the display; (c) a process of identifying one of the plurality of groups having a largest number of the plurality of symbols displayed on the display classified thereto; (d) a process of repositioning the plurality of symbols so that symbols classified into a same group are positioned adjacent to each other; (e) a process of awarding a first prize based on combination of the plurality of symbols positioned on the display; and (f) a process of awarding a second prize in addition to the first prize if the side bet is accepted and simultaneously the one of the plurality of groups selected at the side bet matches the one of the plurality of groups identified at the process (c).
 4. The slot machine according to claim 1, wherein the processor displays a number of symbols classified, with respect to groups having the plurality of symbols positioned on the display classified thereto.
 5. The slot machine according to claim 1, wherein, upon execution of process (b), the processor positions a symbol, using a different display color with respect to groups to be classified.
 6. The slot machine according to claim 1, wherein, upon execution of process (b), the processor positions a symbol, using a different background color with respect to groups to be classified. 